JP4885714B2 - Elastic body inspection method, inspection apparatus, and size prediction program - Google Patents

Abstract

In an inspecting method of a piezoelectric/electrostrictive actuator having a piezoelectric/electrostrictive element and two or more electrodes, the frequency response characteristics is picked up when a vibration is given to the piezoelectric/electrostrictive actuator, and the amount of displacement of the piezoelectric/electrostrictive actuator is predicted by the frequency response characteristics. The piezoelectric/electrostrictive actuator is precisely inspected without dissolution and destruction and without actual driving as a product.

Description

  The present invention relates to an inspection method, an inspection device, and a size prediction program for an elastic body that realizes high accuracy, an inspection method, an inspection device, a displacement amount prediction program for a piezoelectric / electrostrictive actuator, and an inspection for a piezoelectric / electrostrictive sensor. The present invention relates to a method, an inspection apparatus, and a detection sensitivity prediction program.

  In recent years, displacement control devices that adjust optical path lengths and positions on the order of submicrons have been desired in the fields of optics, precision machinery, semiconductor manufacturing, and the like. In response to this, piezoelectric / electrostrictive actuators using strain based on the inverse piezoelectric effect and electrostrictive effect that occur when an electric field is applied to a ferroelectric or antiferroelectric material, and ferroelectric based on similar effects Development of a piezoelectric / electrostrictive device such as a piezoelectric / electrostrictive sensor using charge generation that occurs when stress is applied to a body / antiferroelectric material is underway. This piezoelectric / electrostrictive device is a device that uses electric charges and electric fields induced by electric field induced strain and stress as described above. In particular, the piezoelectric / electrostrictive actuator is an electromagnetic device such as a conventional servo motor or pulse motor. Compared to other systems, it has the features that it is easy to control minute displacement, has high mechanical / electrical energy conversion efficiency, saves power, can be mounted with ultra-precision, and contributes to reducing the size and weight of the product. Its application fields are considered to continue to expand.

  The piezoelectric / electrostrictive actuator has, for example, a lower electrode on one surface of a ceramic substrate formed by integrally forming a thick support portion provided with a cavity and a vibrating portion covering the cavity. , A piezoelectric / electrostrictive body, and a piezoelectric / electrostrictive actuating portion in which an upper electrode is laminated in order. In such a piezoelectric / electrostrictive actuator, when an electric field is generated between the upper electrode and the lower electrode, the piezoelectric / electrostrictive body made of the piezoelectric / electrostrictive material is deformed, and the vibration part is displaced in the vertical direction. Due to the action of displacing the vibration part, the piezoelectric / electrostrictive actuator is applied as an actuator part of a precision instrument. For example, by changing the vibration part up and down, the contact / non-contact of the switch can be controlled, or the micro pump Perform fluid control.

  When a piezoelectric / electrostrictive actuator is used as an actuator for a switch or a micropump, if the amount of displacement is not sufficiently large, the switch will not have a sufficient stroke and will not function as a switch. There has been a problem that the amount of extrusion becomes insufficient or the fluid cannot be extruded at all. Also, when using multiple piezoelectric / electrostrictive actuators in combination, if there is variation in the amount of displacement among the individual actuators, the contact or non-contact operation becomes unstable or the fluid extrusion amount is unstable. The quality of switches and micropumps deteriorates. Accordingly, there is a demand for a piezoelectric / electrostrictive actuator in which the displacement amount of each vibration part is equal to or greater than a certain level and uniform when the same voltage is applied (the same electric field is generated). Therefore, when the piezoelectric / electrostrictive actuator is shipped as a product, it is necessary to directly inspect the displacement amount of the vibration part by a laser Doppler vibrometer or the like. However, when all the lots of the produced piezoelectric / electrostrictive actuators are inspected, the cost becomes high, and thus an inspection method alternative to that is required.

"Vibration Engineering Handbook" (published by Yokendo), 1st edition, published in 1976, Chapter 4 Free Vibration of Distribution System, 4.6 Plate Vibration (P.98-109) "Industrial Fundamental Vibration" (published by Yokendo), 14th edition, published in 1989, Chapter 4 Lateral vibration of flat plate (P.224-228)

  In response to such a request for inspection of a piezoelectric / electrostrictive actuator, conventionally, in the manufacturing process of a piezoelectric / electrostrictive actuator, the capacitance of the piezoelectric / electrostrictive body that is assumed to be a capacitor is measured. The magnitude and uniformity of displacement were inspected when voltage was applied (the same electric field was generated). In this inspection method, since the piezoelectric / electrostrictive body of the piezoelectric / electrostrictive actuator corresponds to the displacement generating portion, if the capacitance is equal, C = εS / d, the electrode area of the piezoelectric / electrostrictive body, the distance between the electrodes, Or, since the dielectric constant and the like are generally equivalent, the displacement amount of the piezoelectric / electrostrictive body (and hence the piezoelectric / electrostrictive operation portion) is also equal, and furthermore, the displacement amount of the vibration portion is also generally equivalent. Based on the idea that the amount of displacement should not vary.

  However, such conventional inspection methods are not always highly accurate. The reason was considered that components other than the piezoelectric / electrostrictive actuator of the piezoelectric / electrostrictive actuator were not reflected in the inspection. In recent piezoelectric / electrostrictive actuators, since the miniaturization has progressed, slight dimensional deviations and variations have a greater effect on the characteristics, and the dimensional deviations and variations are inspected. In order to do this, it is necessary to perform cross-sectional observation with breakage, which requires a great deal of cost. Further, since the inspection needs to be broken, it is impossible to directly inspect the product to be shipped.

  In addition, directly inspecting the amount of displacement of the piezoelectric / electrostrictive actuator with a laser Doppler vibrometer or the like is expensive in apparatus, takes an inspection tact, and increases in cost. In addition, it is necessary to secure a large number of skilled personnel to detect the amount of dimensional deviation and positional deviation from the design value that greatly affects the amount of displacement by visual inspection using a microscope or the like during the manufacturing process. It was costly and expensive. Furthermore, in the method of destructive inspection of dimensional deviation and positional deviation by cross-sectional observation, in addition to high cost, the inspection itself cannot be used as a product, and only a sampling inspection can be performed. These problems also occur in piezoelectric / electrostrictive sensors that require uniform sensor sensitivity with the same design and specifications.

  The present invention has been made in view of the above-described circumstances, and the object of the present invention is to provide a piezoelectric / electrostrictive device (with high accuracy without causing actual driving as a product, without disassembly and destruction) It is to provide a method capable of inspecting a piezoelectric / electrostrictive actuator or a piezoelectric / electrostrictive sensor.

  As a result of repeated research, for example, in the case of the piezoelectric / electrostrictive actuator described above, the amount of displacement of the vibration part depends on the overall rigidity including the base (vibration part and support part), the shape of the vibration part, or the vibration part. It has been found that there is a close relationship between each element relating to the mechanical properties or form of the piezoelectric / electrostrictive actuator, such as the formation position of the piezoelectric / electrostrictive actuator relative to the piezoelectric element.

  As a result of further research, various frequency characteristics when the piezoelectric / electrostrictive actuator is vibrated are examined, and each element related to the mechanical property or form of the piezoelectric / electrostrictive actuator is based on the frequency characteristics. Has been found to be predictable with high accuracy. Then, a system for predicting each element related to the mechanical property or form of the piezoelectric / electrostrictive actuator is constructed, and based on each element related to the mechanical property or form predicted thereby, the high performance of the piezoelectric / electrostrictive actuator is determined. It was found that accurate inspection was possible. Furthermore, since there is a close relationship between the mechanical property or form element and the displacement of the vibration part, the displacement amount of the vibration part of the piezoelectric / electrostrictive actuator can be inspected with high accuracy. I found out.

  Specifically, for example, there is a certain relationship between the value of any frequency characteristic depending on the design dimension of the piezoelectric / electrostrictive actuator and the amount of dimensional deviation or positional deviation from the design dimension value of the subject. It is found that the amount of dimensional deviation and position deviation from the design value in the subject can be inspected within a certain allowable value by obtaining the frequency characteristic value. It was. Since the dimensional deviation from the design value is closely related to the displacement amount characteristic of the piezoelectric / electrostrictive actuator, the displacement amount can be predicted from the frequency characteristic, converted, and inspected. I understood it.

  As a result of repeated research, for example, the dimensional deviation of one part of a piezoelectric / electrostrictive actuator that is a plate (plate-like body) is the height of the resonance peak corresponding to the (1,2) order vibration mode. The dimensional deviations of the other parts are related to the ratio of the resonance frequencies corresponding to the (3, 1) order and (1, 1) order vibration modes. It has been found that there is a resonance of order ((m, n) order) that appears characteristically. Furthermore, there exists a vibration mode of a special order (named as 3.5th order in this specification) that has not yet been described in the conventional literature, and the plate is a plate (plate-like body) due to resonance of the vibration mode. It has been found that the dimensional deviation of one part of the piezoelectric / electrostrictive actuator can be predicted with extremely high accuracy. In addition, these can be inspected individually, and by combining them and creating a calculation formula by multiple regression analysis etc., the displacement amount of the piezoelectric / electrostrictive actuator can be predicted and inspected with high accuracy. Has been found to be possible.

  In general, the vibration of the plate (plate-like body) can be expressed in the form of (m, n) order vibration mode as described in Non-Patent Document 1 and Non-Patent Document 2. For example, in the case of a square or rectangular plate, in the longitudinal direction and the horizontal direction, in the case of a circular plate, in the circumferential direction and the diameter direction, (m, n) according to the number of nodes of the standing wave of vibration, respectively. ) It can be expressed as the following vibration mode. In the present specification, a mode having no node is referred to as primary, and a mode having one node is referred to as secondary. That is, in the case of a rectangular plate, a vibration mode in which there are m−1 nodes in the vertical direction and n−1 in the horizontal direction is expressed as an (m, n) th vibration mode. To specify the vibration mode at each resonance frequency, the plate is vibrated at the resonance frequency, the vibrations at multiple locations on the plate are measured with a laser Doppler vibrometer, etc. It is possible to specify by observing.

  Based on the above concept, it was found that the detection sensitivity of the piezoelectric / electrostrictive sensor can be inspected as well as the displacement amount of the piezoelectric / electrostrictive actuator. Furthermore, it has been found that a structure including a piezoelectric / electrostrictive device (piezoelectric / electrostrictive actuator and piezoelectric / electrostrictive sensor) and having a wide elastic body can be applied as a method for inspecting its dimensions. The invention has been completed. Specifically, the present invention provides the following means.

  That is, according to the present invention, there is provided a method for inspecting an elastic body on a structure having two or more elastic bodies, the frequency characteristic when the structure is vibrated is picked up, and the elastic body An elastic body inspection method for predicting dimensions is provided.

  The frequency characteristics can be obtained by directly measuring mechanical vibration when an elastic body is vibrated with a vibrator, a piezoelectric / electrostrictive element, or the like, using a laser Doppler vibrometer or an acceleration sensor. However, in the case of piezoelectric / electrostrictive actuators and piezoelectric / electrostrictive sensors, it is cheaper and faster to measure the frequency characteristics of electrical impedance, gain and phase using a network analyzer or impedance analyzer. It is possible. This means that all the inventions according to the present invention (in addition to the elastic body inspection method, the piezoelectric / electrostrictive actuator inspection method, the piezoelectric / electrostrictive sensor inspection method, the elastic body inspection apparatus, The same applies to the strain actuator inspection device, the piezoelectric / electrostrictive sensor inspection device, the elastic body size prediction program, the piezoelectric / electrostrictive actuator displacement amount prediction program, and the piezoelectric / electrostrictive sensor detection sensitivity prediction program.

  In the method for inspecting an elastic body according to the present invention, the frequency characteristics include one-order resonance frequency Fx and another-order resonance frequency Fy, and one or more frequency ratios FRxy (FRxy = Fy / Fx) determined by them. ) To one or more frequency differences FDxy (FDxy = Fy−Fx). Furthermore, it is also preferable to predict the dimension of the elastic body by adding the resonance frequency Fz as the frequency characteristic and by any one or a combination of two or more. In the present specification, or means and / or.

  In addition, the peak height PKx, the area Sx, and the difference between the maximum value and the minimum value of the resonance waveform having the frequency characteristic of the first order, and between the resonance waveform of the first order and the resonance waveform of the other order. Of the peak height ratio PKRxy, the peak height difference PKDxy, the area ratio SRxy, the area difference SDxy, the difference between the local maximum value and the local minimum value, and the difference between the local maximum value and the local minimum value. Either is preferable.

  Further, by performing multivariate analysis or the like by combining these frequency characteristics, it is possible to predict and estimate the size of the elastic body with higher accuracy.

  Still further, the elastic body can be easily inspected depending on whether or not a resonance peak related to resonance of a certain order (m, n) appears, that is, whether or not (m, n) order resonance occurs. Yes, this is applicable to all inventions according to the present invention.

  In this specification, the resonance waveform related to the (m, n) -order resonance is the vicinity of the resonance peak corresponding to the (m, n) -order vibration mode among the waveforms shown as frequency characteristics in a predetermined frequency band. Is a waveform (curve). The frequency characteristics include, but are not limited to, mechanical vibration transmission characteristics, electrical impedance characteristics, electrical transmission characteristics, electrical reflection characteristics, etc., where the horizontal axis represents frequency and the vertical axis represents gain. And a phase, impedance and phase, admittance and phase, or the like. Mechanical resonance and electrical resonance are different phenomena, but in piezoelectric / electrostrictive actuators and piezoelectric / electrostrictive sensors, both may be observed at approximately the same resonance frequency. This phenomenon is known and applied to piezoelectric resonators and piezoelectric filters.

  The (m, n) order resonance is specified by a peak-shaped or valley-shaped portion having a peak in the resonance waveform in the chart representing the frequency characteristics. The resonance waveform corresponds to a waveform that represents the vicinity of the peak or valley portion. The area of the resonance waveform is the area of the peaked or valley-shaped portion of the base line having no peak in the frequency characteristic chart, and the peak height of the resonance waveform is the peak of the resonance waveform. This is the peak height value of the shape or valley portion, and the value on the vertical axis may be any frequency characteristic value such as gain, impedance, admittance, phase, etc. In the case of phase and mechanical vibration, it is preferable to take a gain. This is because the base line is relatively flat and data processing is easy. Note that the difference between the maximum value and the minimum value of the resonance waveform is preferably used in the case of a chart that takes the impedance or admittance value as the value on the vertical axis. In the case of impedance or admittance, the baseline is a curve or straight line that rises or falls to the right, and the resonance and anti-resonance are combined, and there are peaks in the peak-shaped part and valley-shaped part. This difference can be used as a characteristic value for predicting the dimensional deviation and displacement.

  The method for inspecting an elastic body according to the present invention is suitably used when the dimension of the elastic body is an amount of deviation between any two elastic bodies out of two or more elastic bodies constituting the structure. Moreover, it is suitably used when the dimension of the elastic body is the undulation amount of any one of the two or more elastic bodies constituting the structure.

  Next, according to the present invention, there is provided a method for inspecting a piezoelectric / electrostrictive actuator comprising a piezoelectric / electrostrictive body and two or more electrodes, and picking up frequency characteristics when the piezoelectric / electrostrictive actuator is vibrated. In addition, the piezoelectric / electrostrictive actuator inspection method for predicting the displacement amount of the piezoelectric / electrostrictive actuator according to the frequency characteristic is provided.

  In the inspection method for a piezoelectric / electrostrictive actuator according to the present invention, the frequency characteristics include one order of resonance frequency Fx and another order of resonance frequency Fy, and one or more frequency ratios FRxy (FRxy) determined by them. = Fy / Fx) to one or more frequency differences FDxy (FDxy = Fy−Fx).

  In the inspection method for a piezoelectric / electrostrictive actuator according to the present invention, the frequency ratio FR of 1 or more and the frequency difference FD of 1 or more, the resonance frequency Fz of 1 or more, or the capacitance CP of the piezoelectric / electrostrictive body. In addition, it is preferable to predict the displacement amount of the piezoelectric / electrostrictive actuator by any one or a combination of two or more.

  Further, the frequency characteristics include the peak height PKx, the area Sx, the difference between the maximum value and the minimum value of the resonance waveform of the first order, and the resonance waveform of the first order and the resonance waveform of another order. Between the peak height ratio PKRxy, the peak height difference PKDxy, the area ratio SRxy, the area difference SDxy, the difference between the local maximum and the local minimum, and the difference between the local maximum and the local minimum It is preferable that it is either.

  In addition, it is possible to predict and estimate the displacement of the piezoelectric / electrostrictive actuator with higher accuracy by combining these frequency characteristics and performing multivariate analysis or the like.

  Next, according to the present invention, there is provided a method for inspecting a piezoelectric / electrostrictive sensor comprising a piezoelectric / electrostrictive body and two or more electrodes, and picking up frequency characteristics when the piezoelectric / electrostrictive sensor is vibrated. In addition, a piezoelectric / electrostrictive sensor inspection method for predicting the detection sensitivity of the piezoelectric / electrostrictive sensor according to the frequency characteristics is provided.

  In the inspection method of the piezoelectric / electrostrictive sensor according to the present invention, the resonance frequency Fx of one order and the resonance frequency Fy of another order, and one or more frequency ratios FRxy (FRxy = Fy / Fx) obtained by them. Or any one or more of the frequency differences FDxy (FDxy = Fy−Fx).

  In the first method for inspecting a piezoelectric / electrostrictive sensor according to the present invention, one or more frequency ratios FRxy to one or more frequency differences FDxy have one or more resonance frequencies Fz to piezoelectric / electrostrictive body static. It is preferable to predict the detection sensitivity of the piezoelectric / electrostrictive sensor by adding the capacitance CP.

  Further, the frequency characteristics include the peak height PKx, the area Sx, the difference between the maximum value and the minimum value of the resonance waveform of the first order, and the resonance waveform of the first order and the resonance waveform of another order. Between the peak height ratio PKRxy, the peak height difference PKDxy, the area ratio SRxy, the area difference SDxy, the difference between the local maximum and the local minimum, and the difference between the local maximum and the local minimum It is preferable that it is either.

  Further, by combining these frequency characteristics and performing multivariate analysis or the like, it is possible to predict and estimate the detection sensitivity of the piezoelectric / electrostrictive sensor with higher accuracy.

  Next, according to the present invention, there is provided an apparatus for inspecting an elastic body applied to a structure having two or more elastic bodies. The apparatus picks up a frequency characteristic when the structure is vibrated. There is provided an inspection apparatus for an elastic body comprising means for predicting a body size.

  In the first elastic body inspection apparatus according to the present invention, the frequency characteristics include one-order resonance frequency Fx and other-order resonance frequency Fy, and one or more frequency ratios FRxy (FRxy = FRxy =) determined by them. Fy / Fx) or one or more frequency differences FDxy (FDxy = Fy−Fx). Furthermore, it is also preferable to include means for predicting the size of the elastic body by adding one or more resonance frequencies Fz as the frequency characteristics and by any one or a combination of two or more.

  In addition, the frequency characteristics include the peak height PKx, the area Sx, the difference between the maximum value and the minimum value of the resonance waveform of the first order, and the resonance waveform of the first order and the resonance waveform of another order. Between the peak height ratio PKRxy, the peak height difference PKDxy, the area ratio SRxy, the area difference SDxy, the difference between the local maximum and the local minimum, and the difference between the local maximum and the local minimum It is preferable that it is either.

  The elastic body inspection apparatus according to the present invention is suitably used when the size of the elastic body is a deviation amount between any two elastic bodies of two or more elastic bodies constituting the structure. Moreover, it is suitably used when the dimension of the elastic body is the undulation amount of any one of the two or more elastic bodies constituting the structure.

  Next, according to the present invention, an apparatus for inspecting a piezoelectric / electrostrictive actuator comprising a piezoelectric / electrostrictive body and two or more electrodes, the frequency characteristics when the piezoelectric / electrostrictive actuator is vibrated are shown. There is provided a piezoelectric / electrostrictive actuator inspection apparatus comprising means for picking up and predicting a displacement amount of the piezoelectric / electrostrictive actuator based on frequency characteristics thereof.

  In the inspection apparatus for a piezoelectric / electrostrictive actuator according to the present invention, the frequency characteristics include the one-order resonance frequency Fx and the other-order resonance frequency Fy, and one or more frequency ratios FRxy (FRxy) determined by them. = Fy / Fx) to one or more frequency differences FDxy (FDxy = Fy−Fx).

  In the piezoelectric / electrostrictive actuator inspection apparatus according to the present invention, the frequency ratio FRxy of 1 or more, the frequency difference FDxy of 1 or more, the resonance frequency Fz of 1 or more, or the capacitance CP of the piezoelectric / electrostrictive body. In addition, it is preferable to include means for predicting the displacement amount of the piezoelectric / electrostrictive actuator by any one or a combination of two or more.

  Further, the frequency characteristics include the peak height PKx, the area Sx, the difference between the maximum value and the minimum value of the resonance waveform of the first order, and the resonance waveform of the first order and the resonance waveform of another order. Between the peak height ratio PKRxy, the peak height difference PKDxy, the area ratio SRxy, the area difference SDxy, the difference between the local maximum and the local minimum, and the difference between the local maximum and the local minimum It is preferable that it is either.

  Next, according to the present invention, an apparatus for inspecting a piezoelectric / electrostrictive sensor comprising a piezoelectric / electrostrictive body and two or more electrodes, the frequency characteristics when the piezoelectric / electrostrictive sensor is vibrated are shown. There is provided a piezoelectric / electrostrictive sensor inspection apparatus comprising means for picking up and predicting the detection sensitivity of the piezoelectric / electrostrictive sensor based on the frequency characteristics thereof.

  In the piezoelectric / electrostrictive sensor inspection apparatus according to the present invention, the frequency characteristics include one-order resonance frequency Fx and other-order resonance frequency Fy, and one or more frequency ratios FRxy (FRxy = FRxy =) determined by them. Fy / Fx) or one or more frequency differences FDxy (FDxy = Fy−Fx).

  In the first piezoelectric / electrostrictive sensor inspection apparatus according to the present invention, the one or more frequency ratios FRxy to one or more frequency differences FDxy have one or more resonance frequencies Fz to the piezoelectric / electrostrictive body static. It is preferable to provide means for predicting the detection sensitivity of the piezoelectric / electrostrictive sensor by adding the capacitance CP.

  Further, the frequency characteristics include the peak height PKx, the area Sx, the difference between the maximum value and the minimum value of the resonance waveform of the first order, and the resonance waveform of the first order and the resonance waveform of another order. Between the peak height ratio PKRxy, the peak height difference PKDxy, the area ratio SRxy, the area difference SDxy, the difference between the local maximum and the local minimum, and the difference between the local maximum and the local minimum It is preferable that it is either.

  Next, according to the present invention, in order to predict the size of the elastic body according to the structure having two or more elastic bodies, the computer inputs the measurement value of the frequency characteristic of the structure whose predicted size is to be calculated. Of the elastic body for functioning as means for obtaining the predicted size of the elastic body applied to the structure based on the calculation formula of the predicted size, and for outputting the predicted size of the elastic body applied to the obtained structure. A dimension prediction program is provided.

  The elastic body size prediction program according to the present invention is preferably used when the predicted elastic body size is a deviation amount between any two elastic bodies of two or more elastic bodies constituting the structure. Used. Moreover, it is suitably used when the predicted size of the elastic body is the amount of swell of any one of the two or more elastic bodies constituting the structure.

  More specifically, the elastic body size prediction program according to the present invention is a computer program that causes a computer to vibrate in order to predict the size of an elastic body according to a structure having two or more elastic bodies. Means for inputting primary resonance frequency F1 (the above frequency characteristic), means for inputting one or more higher order nth order resonance frequencies Fn (the above frequency characteristics) when the structure is vibrated, and primary resonance frequency Means for obtaining a frequency ratio FRn (FRn = Fn / F1) of one or more by F1 and one or more higher-order n-th order resonance frequencies Fn, applied to the structure based on Formula 1 (calculation formula of the predicted dimensions) It is preferable to function as means for obtaining the predicted dimensions of the elastic body and means for outputting the predicted dimensions of the elastic body according to the obtained structure.

  The elastic body size prediction program according to the present invention is more preferably one or more when the computer is vibrated to predict the size of the elastic body according to the structure having two or more elastic bodies. Means for inputting the m-th order resonance frequency Fm (the above frequency characteristic), means for obtaining the predicted dimension of the elastic body on the structure based on Formula 2 (the formula for calculating the predicted dimension), and the obtained structure It is preferable to function as a means for outputting the predicted size of the elastic body.

  Next, according to the present invention, in order to predict the displacement amount of the piezoelectric / electrostrictive actuator including the piezoelectric / electrostrictive body and two or more electrodes, the computer calculates the predicted displacement amount. Means for inputting the frequency characteristics of the electrostrictive actuator, means for obtaining the predicted displacement of the piezoelectric / electrostrictive actuator based on a calculation formula of the predicted displacement, means for outputting the predicted displacement of the obtained piezoelectric / electrostrictive actuator, As described above, a displacement prediction program for a piezoelectric / electrostrictive actuator for functioning is provided.

  In the displacement prediction program for a piezoelectric / electrostrictive actuator according to the present invention, the area, the peak height, and the maximum of the resonance waveform relating to the first-order resonance or one or more higher-order n-th resonances as the frequency characteristics. The difference between the value and the minimum value, and the area ratio, the peak height ratio, between the resonance waveform relating to the first-order resonance and the resonance waveform relating to the one or more higher-order n-order resonances, And the ratio of the difference between the maximum value and the minimum value can be input.

  In addition, the displacement prediction program for a piezoelectric / electrostrictive actuator according to the present invention more specifically relates to a piezoelectric / electrostrictive actuator comprising a piezoelectric / electrostrictive body and two or more electrodes according to the present invention. In order to predict the amount of displacement, the computer inputs means for inputting a primary resonance frequency F1 (the above frequency characteristic) when the piezoelectric / electrostrictive actuator is vibrated, and 1 when the piezoelectric / electrostrictive actuator is vibrated. The means for inputting the above higher-order nth-order resonance frequency Fn (the above-mentioned frequency characteristic), the first-order resonance frequency F1 and the one or more higher-order n-order resonance frequencies Fn provide one or more frequency ratios FRn (FRn = Fn). / F1), a means for obtaining a predicted displacement amount of the piezoelectric / electrostrictive actuator based on Formula 3 (the calculation formula for the predicted displacement amount), and a predicted displacement amount of the obtained piezoelectric / electrostrictive actuator are output. That means, as, it is preferable that to function.

  The displacement prediction program for a piezoelectric / electrostrictive actuator according to the present invention still further predicts the displacement amount of a piezoelectric / electrostrictive actuator including a piezoelectric / electrostrictive body and two or more electrodes according to the present invention. In order to do this, the computer inputs means for inputting a primary resonance frequency F1 (the above frequency characteristic) when the piezoelectric / electrostrictive actuator is vibrated, and one or more higher orders when the piezoelectric / electrostrictive actuator is vibrated. Means for inputting the n-th order resonance frequency Fn (the above frequency characteristic), means for inputting the capacitance CP of the piezoelectric / electrostrictive body, the first order resonance frequency F1, and one or more higher order n order resonance frequencies Fn. Means for obtaining a frequency ratio FRn (FRn = Fn / F1) of 1 or more, means for obtaining a predicted displacement amount of the piezoelectric / electrostrictive actuator based on Formula 4 (calculation formula of the predicted displacement amount), and obtained piezoelectric / Electrostriction Means for outputting the predicted displacement of the actuator as, it is preferable that to function.

  The displacement prediction program for a piezoelectric / electrostrictive actuator according to the present invention further includes a computer for predicting the displacement of a piezoelectric / electrostrictive actuator including a piezoelectric / electrostrictive body and two or more electrodes. , Means for inputting one or more m-th order resonance frequencies Fm (the above frequency characteristics) when the piezoelectric / electrostrictive actuator is vibrated, the piezoelectric / electrostrictive actuators based on Formula 5 (the above formula for calculating the predicted displacement) It is preferable to function as a means for obtaining the predicted displacement amount and a means for outputting the predicted displacement amount of the obtained piezoelectric / electrostrictive actuator.

  The displacement prediction program for a piezoelectric / electrostrictive actuator according to the present invention further includes a computer for predicting the displacement of a piezoelectric / electrostrictive actuator including a piezoelectric / electrostrictive body and two or more electrodes. , Means for inputting a primary resonance frequency F1 (the above frequency characteristic) when the piezoelectric / electrostrictive actuator is vibrated, one or more higher-order n-order resonance frequencies Fn when the piezoelectric / electrostrictive actuator is vibrated The frequency ratio FRn (FRn = FRn = FRn = the frequency characteristic) and the mth order resonance frequency Fm (the frequency characteristic) are input by means of the primary resonance frequency F1 and the one or more higher order nth order resonance frequencies Fn. Fn / F1), a means for obtaining a predicted displacement amount of the piezoelectric / electrostrictive actuator based on Formula 6 (the calculation formula for the predicted displacement amount), and a prediction of the obtained piezoelectric / electrostrictive actuator. It means for outputting a displacement amount, as, it is preferable that to function.

  The displacement prediction program for a piezoelectric / electrostrictive actuator according to the present invention further includes a computer for predicting the displacement of a piezoelectric / electrostrictive actuator including a piezoelectric / electrostrictive body and two or more electrodes. , Means for inputting a primary resonance frequency F1 (the above frequency characteristic) when the piezoelectric / electrostrictive actuator is vibrated, one or more higher-order n-order resonance frequencies Fn when the piezoelectric / electrostrictive actuator is vibrated (Frequency characteristics) and means for inputting the m-th order resonance frequency Fm (the frequency characteristics), means for inputting the capacitance CP of the piezoelectric / electrostrictive body, the first order resonance frequency F1 and one or more higher order n Means for obtaining a frequency ratio FRn (FRn = Fn / F1) of 1 or more by the next resonance frequency Fn, the predicted displacement amount of the piezoelectric / electrostrictive actuator is obtained based on the equation (7) (predicted displacement calculation formula). Stage means for outputting the predicted displacement of the resultant piezoelectric / electrostrictive actuator, as, it is preferable that to function.

  Next, according to the present invention, in order to predict the detection sensitivity of a piezoelectric / electrostrictive sensor including a piezoelectric / electrostrictive body and two or more electrodes, a computer is used to calculate the predicted detection sensitivity. Means for inputting frequency characteristics of the electrostrictive sensor, means for obtaining the predicted detection sensitivity of the piezoelectric / electrostrictive sensor based on a calculation formula of the predicted detection sensitivity, means for outputting the predicted detection sensitivity of the obtained piezoelectric / electrostrictive sensor, As described above, a detection sensitivity prediction program for a piezoelectric / electrostrictive sensor for functioning is provided.

  In the detection sensitivity prediction program for a piezoelectric / electrostrictive sensor according to the present invention, the area, the peak height, and the maximum of the resonance waveform relating to the first-order resonance or one or more higher-order n-th resonances as the frequency characteristics. The difference between the value and the minimum value, and the area ratio, the peak height ratio, between the resonance waveform relating to the first-order resonance and the resonance waveform relating to the one or more higher-order n-order resonances, And the ratio of the difference between the maximum value and the minimum value can be input.

  More specifically, the piezoelectric / electrostrictive sensor detection sensitivity prediction program according to the present invention predicts the detection sensitivity of a piezoelectric / electrostrictive sensor including a piezoelectric / electrostrictive body and two or more electrodes. Means for inputting a primary resonance frequency F1 (the above frequency characteristic) when the piezoelectric / electrostrictive sensor is vibrated in the computer; one or more higher-order n-th resonances when the piezoelectric / electrostrictive sensor is vibrated Means for inputting frequency Fn (the above-mentioned frequency characteristic), means for obtaining a frequency ratio FRn (FRn = Fn / F1) of 1 or more by a primary resonance frequency F1 and one or more high-order n-order resonance frequencies Fn, a number It functions as a means for obtaining the predicted detection sensitivity of the piezoelectric / electrostrictive sensor based on the eight formulas (the calculation formula for the predicted detection sensitivity) and a means for outputting the predicted detection sensitivity of the obtained piezoelectric / electrostrictive sensor. Preferably there is.

  The program for predicting the detection sensitivity of a piezoelectric / electrostrictive sensor according to the present invention further predicts the detection sensitivity of a piezoelectric / electrostrictive sensor comprising a piezoelectric / electrostrictive body and two or more electrodes according to the present invention. In order to do this, the computer inputs means for inputting the primary resonance frequency F1 (the above frequency characteristic) when the piezoelectric / electrostrictive sensor is vibrated, and one or more higher orders when the piezoelectric / electrostrictive sensor is vibrated. Means for inputting the n-th order resonance frequency Fn (the above frequency characteristic), means for inputting the capacitance CP of the piezoelectric / electrostrictive body, the first order resonance frequency F1, and one or more higher order n order resonance frequencies Fn. Means for obtaining a frequency ratio FRn (FRn = Fn / F1) of 1 or more, means for obtaining the predicted detection sensitivity of the piezoelectric / electrostrictive sensor based on Formula 9 (calculation formula of the predicted detection sensitivity), and the obtained piezoelectric / The hand that outputs the predicted detection sensitivity of the electrostrictive sensor As, it is preferable that to function.

  Each mathematical expression in the invention of each program according to the present invention is a mathematical expression that can be used in the invention of each method. For example, the (first) elastic body inspection method according to the present invention predicts the size of the elastic body from a frequency ratio FRn of 1 or more. 1) Equation 1 of the elastic body size prediction program can be used.

  According to the elastic body inspection method and inspection apparatus of the present invention, a part of a structure including two or more elastic bodies is not used as a criterion for inspection, but the entire structure is minutely vibrated. The resonance frequency of one order, the resonance frequency of other orders, and the frequency ratio or frequency difference obtained by them, and the peak height, area, maximum value and minimum value of the resonance waveform of the first order Structure based on the difference in values and the peak height ratio, peak height difference, area ratio, area difference, etc. between the resonance waveform of one order and the resonance waveform of the other order Since the dimensions of the elastic body such as the amount of displacement between the two elastic bodies of the body and the amount of waviness of the elastic body 1 are predicted, the inspection can be performed with high accuracy without depending on experience. And since it is a nondestructive inspection, a more accurate pass / fail judgment can be made quickly.

  The piezoelectric / electrostrictive actuator inspection method and inspection apparatus according to the present invention includes a piezoelectric / electrostrictive body that is a part of a piezoelectric / electrostrictive actuator including a piezoelectric / electrostrictive body and two or more electrodes as constituent elements. When the entire piezoelectric / electrostrictive actuator is actually vibrated, the resonance frequency of the first order, the resonance frequency of the other order, and the frequency ratio required by them are not used for the inspection. To the frequency difference and the peak height, area, difference between the maximum value and the minimum value of the resonance waveform of the first order, and the peak between the resonance waveform of the first order and the resonance waveform of the other order. Since the displacement of the piezoelectric / electrostrictive actuator is predicted based on the height ratio, peak height difference, area ratio, area difference, etc., it is possible to inspect with high accuracy without relying on experience. I can do it. And since it is a nondestructive inspection, a more accurate pass / fail judgment can be made quickly. Therefore, an error in shipping an undesired product can be prevented.

  The inspection method and inspection apparatus for a piezoelectric / electrostrictive sensor according to the present invention includes a piezoelectric / electrostrictive body that is a part of a piezoelectric / electrostrictive sensor including a piezoelectric / electrostrictive body and two or more electrodes as constituent elements. When the entire piezoelectric / electrostrictive sensor is actually vibrated, the resonance frequency of the first order, the resonance frequency of the other order, and the frequency ratio required by them are not used for the inspection. To the frequency difference and the peak height, area, difference between the maximum value and the minimum value of the resonance waveform of the first order, and the peak between the resonance waveform of the first order and the resonance waveform of the other order. Since the detection sensitivity of the piezoelectric / electrostrictive sensor is predicted based on the height ratio, peak height difference, area ratio, area difference, etc., inspection can be performed with high accuracy without relying on experience. I can do it. And since it is a nondestructive inspection, a more accurate pass / fail judgment can be made quickly. Therefore, an error in shipping an undesired product can be prevented.

It is a figure which shows an example of a piezoelectric / electrostrictive actuator, and is a perspective view which isolate | separates and represents a vibration part and a support part. It is sectional drawing showing the AA 'cross section containing the vibration part and piezoelectric / electrostrictive action | operation part of the piezoelectric / electrostrictive actuator shown by FIG. FIG. 2 is a cross-sectional view showing a BB ′ cross section including a vibration part and a piezoelectric / electrostrictive operation part of the piezoelectric / electrostrictive actuator shown in FIG. FIG. 4 is a cross-sectional view illustrating an example of a piezoelectric / electrostrictive actuator in which a base body and a piezoelectric / electrostrictive operation unit are displaced, and a cross-sectional view corresponding to FIG. FIG. 4 is a cross-sectional view showing a piezoelectric / electrostrictive actuator having a vibrating portion having a downward swell (in the drawing), and a cross-section corresponding to FIG. 3. It is sectional drawing which shows the example which applied the piezoelectric / electrostrictive actuator as an actuator part of a microswitch, and represents the non-conduction state (OFF). It is sectional drawing which shows the example which applied the piezoelectric / electrostrictive actuator as an actuator part of a microswitch, and represents the conduction | electrical_connection state (ON). It is sectional drawing which shows an example of a piezoelectric / electrostrictive actuator. It is sectional drawing which shows an example of a piezoelectric / electrostrictive actuator. It is a figure which shows an example of a piezoelectric / electrostrictive actuator, and is sectional drawing which shows the piezoelectric / electrostrictive actuator of a form with the lateral deviation of the distance D. It is a figure which shows an example of a piezoelectric / electrostrictive actuator, and is sectional drawing which shows the piezoelectric / electrostrictive actuator of a form with an upward wave | undulation (in the figure) of the amount of waviness. It is a figure which shows an example of a piezoelectric / electrostrictive actuator, and is sectional drawing which shows the form of the piezoelectric / electrostrictive actuator of the form which has the lateral deviation of the distance D, and the upward wave | undulation (in the figure) of the wave amount H. It is sectional drawing which shows an example of a piezoelectric / electrostrictive actuator. It is a figure which shows an example of a piezoelectric / electrostrictive actuator, and is a perspective view which isolate | separates and represents a vibration part and a support part. It is sectional drawing which shows CC 'cross section in FIG. It is a perspective view which shows an example of a piezoelectric / electrostrictive actuator. It is a perspective view which shows an example of a piezoelectric / electrostrictive actuator. It is a top view which shows an example of the shape of the vibration part of a piezoelectric / electrostrictive actuator. It is a top view which shows an example of the shape of the vibration part of a piezoelectric / electrostrictive actuator. It is a top view which shows an example of the shape of the vibration part of a piezoelectric / electrostrictive actuator. It is a top view which shows an example of the shape of the vibration part of a piezoelectric / electrostrictive actuator. It is a top view which shows an example of the shape of the vibration part of a piezoelectric / electrostrictive actuator. It is a block diagram which shows an example of a frequency characteristic measurement system. It is a block diagram which shows an example of a frequency characteristic measurement system. It is a block diagram which shows an example of a frequency characteristic measurement system. It is a block diagram which shows an example of a frequency characteristic measurement system. It is a block diagram which shows an example of a frequency characteristic measurement system. It is explanatory drawing which shows the vibration mode of a rectangular board. It is explanatory drawing which shows the vibration mode of a circular board. It is the figure which showed the vibration distribution of the primary vibration mode. It is the figure which showed the vibration distribution of the high order peak A vibration mode. It is the figure which showed the vibration distribution of the high order peak B vibration mode. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a chart which shows an example of the frequency characteristic of a piezoelectric / electrostrictive actuator. It is a graph which shows the relationship between the deviation | shift amount of the piezoelectric / electrostrictive body concerning a piezoelectric / electrostrictive actuator, and a vibration part, and the displacement amount of the piezoelectric / electrostrictive actuator which has the deviation | shift amount. It is a graph which shows the relationship between frequency ratio FR1A and the lateral shift amount (absolute value) of a piezoelectric / electrostrictive body and a vibration part. It is a graph which shows the relationship between lateral deviation | shift amount and the height of a peak (resonance waveform). It is a graph which shows the relationship between lateral deviation | shift amount and an area (resonance waveform). 5 is a graph showing a relationship between a lateral deviation amount and a peak height ratio (between resonance waveforms) and a lateral deviation amount and an area ratio (between resonance waveforms). It is a graph which shows the relationship between the amount of waviness of the vibration part concerning a piezoelectric / electrostrictive actuator, and the amount of displacement of the piezoelectric / electrostrictive actuator which has the amount of waviness. It is a graph which shows the relationship between frequency ratio FR1B and the amount of waviness of the vibration part concerning a piezoelectric / electrostrictive actuator. It is a graph which shows the relationship between frequency ratio FRDE and the amount of waviness of the vibration part concerning a piezoelectric / electrostrictive actuator. It is a graph of the predicted displacement amount and the measured displacement amount when the displacement is predicted by a linear expression of only the capacity CP. It is a graph which shows the relationship between the prediction displacement amount at the time of estimating a displacement using a frequency characteristic, and measured displacement amount. It is a block diagram which shows an example of the computer system in which the displacement amount prediction program of the piezoelectric / electrostrictive actuator which concerns on this invention was integrated. It is a block diagram which shows an example of the computer system in which the displacement amount prediction program of the piezoelectric / electrostrictive actuator which concerns on this invention was integrated.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Central processing unit, 2 ... Memory | storage device, 4 ... Input device, 5 ... Output device, 10 ... Computer system, 20, 30, 40, 50, 51 ... Piezoelectric / electrostrictive actuator, 44 ... Base | substrate, 46 ... Cavity, 66: vibrating portion, 68: support portion, 73: intermediate electrode, 75 ... upper electrode, 77 ... lower electrode, 78 ... piezoelectric / electrostrictive operating portion, 79 ... piezoelectric / electrostrictive body.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. However, the present invention should not be construed as being limited to these, and those skilled in the art will be able to do so without departing from the scope of the present invention. Various changes, modifications and improvements can be made based on the knowledge. For example, the drawings show preferred embodiments of the present invention, but the present invention is not limited by the modes shown in the drawings or the information shown in the drawings. In practicing or verifying the present invention, means similar to or equivalent to those described in the present specification can be applied, but preferred means are those described below. In the present specification, when simply referring to the present invention, the elastic body inspection method, inspection apparatus, and size prediction program, the piezoelectric / electrostrictive actuator inspection method, inspection apparatus, displacement amount prediction program, and A piezoelectric / electrostrictive sensor inspection method, inspection apparatus, and detection sensitivity prediction program are all referred to.

  First, piezoelectric / electrostrictive actuators that can be the targets of the piezoelectric / electrostrictive actuator inspection method, inspection apparatus, and displacement prediction program according to the present invention will be described. 1, FIG. 2, FIG. 3, FIG. 4, and FIG. 5 are diagrams showing an example of a piezoelectric / electrostrictive actuator. FIG. 1 is a perspective view in which the vibration part 66 and the support part 68 are separated, and FIG. 2 is a cross-sectional view showing the AA ′ cross section of FIG. 1 including the vibration part 66 and the piezoelectric / electrostrictive operation part 78. 3 is a cross-sectional view showing the BB ′ cross-section of FIG. 1 in the same manner. The illustrated piezoelectric / electrostrictive actuator 20 includes a base 44 and a piezoelectric / electrostrictive operating portion 78. The base 44 is formed by integrally forming a thick support portion 68 having a cavity 46 and a vibrating portion 66 that covers the cavity 46. The piezoelectric / electrostrictive operation unit 78 includes a piezoelectric / electrostrictive body 79, an upper electrode 75 formed on one surface thereof, and a lower electrode 77 formed on the other surface, and the lower electrode 77 vibrates. It is disposed on one surface of the base body 44 so as to contact the portion 66. A piezoelectric / electrostrictive actuator has such a structure. Usually, a base and a piezoelectric / electrostrictive body are formed of a ceramic material (piezoelectric / electrostrictive material), and an electrode is formed of a metal material (conductive material). Since these are elastic materials, the piezoelectric / electrostrictive body, the base and the like correspond to the elastic body, and the piezoelectric / electrostrictive actuator corresponds to a structure having two or more elastic bodies.

  In the piezoelectric / electrostrictive actuator 20, when an electric field is generated between the upper electrode 75 and the lower electrode 77, the piezoelectric / electrostrictive body 79 made of a piezoelectric / electrostrictive material is displaced, and the vibrating portion 66 is deformed. Due to this action, the piezoelectric / electrostrictive actuator 20 is applied as, for example, an actuator part of a precision instrument. 6A and 6B are cross-sectional views showing an example in which a piezoelectric / electrostrictive actuator is applied as an actuator portion of a microswitch. In the illustrated microswitch 120, the switch electrode 18 is provided in the cavity 46 of the piezoelectric / electrostrictive actuator 20, and a terminal plate 121 is attached so as to close the cavity 46, and the terminal plate 121 is opposed to the switch electrode 18. Thus, the switch electrode 19 is provided. If the vibration part 66 is not deformed, the switch electrodes 18 and 19 are non-conductive (OFF) (see FIG. 6A), but when the piezoelectric / electrostrictive body 79 is displaced and the vibration part 66 is deformed. The switch electrodes 18 and 19 are turned on (see FIG. 6B).

  As a piezoelectric / electrostrictive actuator, in addition to the piezoelectric / electrostrictive actuator 20 having a single layer of piezoelectric / electrostrictive body, piezoelectric / electrostrictive actuators 70, 30, 40 whose sectional views are shown in FIGS. Is exemplified. 7 is a cross-sectional view showing a cross section according to FIG. 2, and FIGS. 8 and 12 are cross-sectional views showing a cross section according to FIG. The piezoelectric / electrostrictive actuators 70, 30, and 40 shown in FIGS. 7, 8, and 12 include a base 44 and a piezoelectric / electrostrictive actuator 78, and the base 44 has a thick support having a cavity 46. The piezoelectric / electrostrictive actuator 70 and the piezoelectric / electrostrictive actuator 30 (see FIG. 6) are common to the piezoelectric / electrostrictive actuator 20 in that the portion 68 and the vibrating portion 66 covering the cavity 46 are integrally formed. 7 and FIG. 8) has two layers of piezoelectric / electrostrictive bodies 79 sandwiched between an upper electrode 75, an intermediate electrode 73 and a lower electrode 77, and the piezoelectric / electrostrictive actuator 40 (see FIG. 12) is similarly piezoelectric. / It differs in having three layers of electrostrictive bodies 79. In this specification, for the sake of convenience, the electrode that is closest to the vibration part of the piezoelectric / electrostrictive actuator is referred to as the lower electrode, and the electrode that is farthest from the vibration part is referred to as the upper electrode. When the strain bodies are laminated, an electrode other than the upper electrode and the lower electrode is referred to as an intermediate electrode.

  FIG. 15A and FIG. 15B are perspective views illustrating aspects of the substrate of the piezoelectric / electrostrictive actuator. Like the piezoelectric / electrostrictive actuator 50 shown in FIG. 15 (a), a vibrating part 66 having a piezoelectric / electrostrictive actuating part 78 provided on one surface is supported by support parts 68 on both sides, and the cavity 46 is formed. It is also possible to form the base body 44 by forming it, and like the piezoelectric / electrostrictive actuator 51 shown in FIG. 15 (b), the vibration part 66 provided with the piezoelectric / electrostrictive operating part 78 on one surface includes: A cantilever configuration in which the base 44 is supported by the support portion 68 only on one side thereof may be used. As described above, the piezoelectric / electrostrictive actuator is not limited, but a piezoelectric / electrostrictive operating unit that generates a displacement is provided on one surface of the vibrating unit. Therefore, when a large displacement is required, it is preferable that the other surface side of the vibrating part is not constrained and is free in order to facilitate deformation. In addition, when a strong generating force or a high-speed response is required, a dual-support mode (see FIG. 15A) that supports both ends of the piezoelectric / electrostrictive operation unit is preferable.

  FIG. 16A to FIG. 16E are top views illustrating the shape of the vibrating portion 66. As the shape seen from the upper surface of the thin plate-like vibrating portion 66, a square (FIG. 16 (a)), a rectangle (FIG. 16 (b)), a circle (FIG. 16 (c)), and an oval (FIG. 16 (d)). A hexagon (polygon, FIG. 16 (e)) is exemplified. For example, in the case of a circular shape (FIG. 16 (c)), the entire circumference may be supported by the support portion 68, and is supported by the support portion 68 at two opposing portions or one portion of the periphery. Also good. As described above, the piezoelectric / electrostrictive actuator does not limit the shape of the vibrating portion 66.

  Next, a method for manufacturing the piezoelectric / electrostrictive actuator will be described by taking the case of the piezoelectric / electrostrictive actuator 20 as an example. When manufacturing a piezoelectric / electrostrictive actuator, if a ceramic material is used for the substrate, it can be manufactured using a green sheet laminating method, and the piezoelectric / electrostrictive actuator uses a film forming method such as a thin film or a thick film. Can be manufactured.

  The base 44 is manufactured as follows. For example, a ceramic powder such as zirconium oxide is added and mixed with a binder, a solvent, a dispersant, a plasticizer, and the like to prepare a slurry. A green sheet having a thickness is prepared. Then, the green sheet is processed into various required shapes by a method such as punching using a mold or laser processing. Then, after sequentially superposing a plurality of green sheets, a ceramic green laminate is obtained by, for example, heat-bonding. When the obtained green sheet laminate is fired at a temperature of about 1200 to 1600 ° C., a base 44 is obtained.

  Subsequently, a piezoelectric / electrostrictive operation portion 78 is formed on one surface of the base 44. For example, the lower electrode 77 is printed at a predetermined position on one surface of the substrate 44 by a film forming method such as a screen printing method, fired at a temperature of about 1250 to 1450 ° C., and then the piezoelectric / electrostrictive body 79 is printed. The piezoelectric / electrostrictive operating portion 78 can be formed by firing at a temperature of about 1100 to 1350 ° C. and then printing the upper electrode 75 and preferably firing at a temperature of 500 to 900 ° C. Thereafter, an electrode lead for connecting the electrode to the drive circuit may be printed and fired. By selecting an appropriate material, each electrode of the piezoelectric / electrostrictive operating portion, the piezoelectric / electrostrictive body, and the electrode lead can be sequentially printed, and then integrally fired once.

  After the piezoelectric / electrostrictive actuator 20 is formed as described above, when the piezoelectric / electrostrictive actuator 20 needs to be polarized, a polarization process is performed. The polarization is performed, for example, by applying a voltage (polarization voltage) sufficiently higher than the drive voltage to be used between the upper electrode 75 and the lower electrode 77. Although not limited, when the drive voltage is 30V, the polarization voltage is set to about 70V. Then, the piezoelectric / electrostrictive actuator 20 subjected to the polarization process is inspected to confirm whether or not the base body 44 and the piezoelectric / electrostrictive operating portion 78 are normally manufactured. If the base 44 and the piezoelectric / electrostrictive operating portion 78 are displaced or the vibrating portion 66 is wavy, a desired amount of displacement may not be obtained even if the same (driving) voltage is applied between the electrodes.

  FIG. 4 is a cross-sectional view showing an example of a piezoelectric / electrostrictive actuator in which the piezoelectric / electrostrictive actuating portion 78 is laterally displaced with respect to the base 44, and shows a piezoelectric / electrostrictive actuator in which lateral displacement is not generated. It is the figure by which the cross section corresponding to was shown. As described above, even if the production is sufficiently controlled, it is inevitable that a certain amount of lateral deviation occurs as a variation. The reasons for the occurrence of this lateral shift include that there is a limit to the positioning accuracy during screen printing and that the screen plate making used for screen printing is stretched. In many cases, the piezoelectric / electrostrictive actuator 20 shown in FIG. 3 is manufactured and used as a plurality of sets. Even when the piezoelectric / electrostrictive actuator 20 is divided into one, the production efficiency is improved. Are manufactured as a plurality of sets (three examples are shown in FIG. 13, but usually several tens or more). For example, the lower electrode 77, the piezoelectric / electrostrictive body 79, and the upper portion are formed on one surface of the base body 44 provided with a plurality of cavities 46 by screen printing using a conductive material paste and a piezoelectric / electrostrictive material paste. The electrode 75 is printed, and a plurality of piezoelectric / electrostrictive operation portions 78 are formed. At that time, the relative position between the base body 44 (cavity 46) and the piezoelectric / electrostrictive body 79 or the like is not uniform in all the piezoelectric / electrostrictive actuators for the above reasons, and a lateral shift may occur. FIG. 14 is a cross-sectional view showing a CC ′ cross-section in FIG. 13, and is a diagram showing an example in which a plurality of piezoelectric / electrostrictive operation parts are unevenly displaced. In FIG. 14, the piezoelectric / electrostrictive operating portion 78 on the left side in the drawing is not laterally displaced with respect to the cavity 46, but the central piezoelectric / electrostrictive operating portion 78 in the drawing is slightly laterally displaced with respect to the cavity 46. The piezoelectric / electrostrictive actuating portion 78 on the right side in FIG.

  Specifically, the dimensions of the piezoelectric / electrostrictive actuator 20 (corresponding to a structure having two or more elastic bodies), which is a predicted item in the inspection, are the above-described lateral displacement amounts, that is, the piezoelectric / electrostrictive actuator 78. In addition to the amount of lateral displacement between the piezoelectric / electrostrictive body 79 (corresponding to the elastic body) and the vibration part 66 of the base body 44 (corresponding to the elastic body), the amount of swell of the vibration part 66 of the base body 44 can be mentioned. FIG. 5 is a cross-sectional view showing a piezoelectric / electrostrictive actuator in which the vibrating portion 66 has a downward undulation in FIG. In the present specification, the swell amount H (see FIG. 5) is defined as positive (plus) upward swell. That is, the piezoelectric / electrostrictive actuator shown in FIG. 5 has a negative undulation amount.

  Next, with reference to FIG. 9, FIG. 10, and FIG. 11, the amount of lateral displacement between the piezoelectric / electrostrictive body 79 and the vibrating portion 66 will be described. 9, FIG. 10 and FIG. 11 are diagrams showing a piezoelectric / electrostrictive actuator having two layers of piezoelectric / electrostrictive bodies 79, including a vibrating part and a piezoelectric / electrostrictive operating part, according to FIG. FIG. FIG. 9 shows a form in which there is a lateral shift of a distance D (μm). FIG. 10 shows a form in which there is upward undulation in the figure of the undulation amount H (μm). FIG. 11 shows a form in which there is a lateral shift of the distance D (μm) and an upward undulation of the undulation amount H (μm). 9 and 11, when the lateral displacement amount is changed (that is, the distance D is changed), the piezoelectric / electrostrictive body 79 of the piezoelectric / electrostrictive actuating portion 78 that is a displacement generating portion and the vibrating portion 66 overlap each other (piezoelectric). The area of the piezoelectric / electrostrictive actuator can be changed by changing the area. In this piezoelectric / electrostrictive actuator, since the cavity length of the BB ′ section is very small compared to the length of the cavity of the AA ′ section, the device characteristics are easily affected by the lateral shift amount in the BB ′ section. In this specification, the amount of lateral deviation between the piezoelectric / electrostrictive body 79 and the vibrating portion 66 refers to the amount of deviation in the BB ′ cross section shown in FIG. The lateral deviation amounts shown in FIGS. 9 and 11 are similar lateral deviation amounts.

  Next, an apparatus for picking up frequency characteristics by vibrating an elastic body or a piezoelectric / electrostrictive device (piezoelectric / electrostrictive actuator or piezoelectric / electrostrictive sensor) will be described. FIG. 17A is a configuration diagram showing a system for picking up frequency characteristics by vibrating with an external force. This frequency characteristic measurement system mainly includes an exciter 211, a laser vibrometer 212, an FFT analyzer 213, and an amplifier 214. For example, the piezoelectric / electrostrictive actuator 210 is fixed to the vibrator 211 with a double-sided tape or an adhesive, and is vibrated. The vibration is measured by the laser vibrometer 212, the vibration is analyzed by the FFT analyzer 213, and the frequency characteristic is determined. Can be picked up. The amplifier 214 serves to amplify the signal of the FFT analyzer 213 in order to drive the vibrator. A gain phase analyzer, a frequency analyzer, etc. can be used instead of the FFT analyzer, and an acceleration sensor can be used instead of the laser vibrometer. According to such a frequency characteristic measurement system, not any piezoelectric / electrostrictive device that can be vibrated by applying a voltage, but any structure that has two or more elastic bodies that cannot vibrate with electric force is vibrated. The frequency characteristic can be picked up, and the size of the elastic body applied to the structure can be predicted by the frequency characteristic.

  FIG. 17B is a configuration diagram showing a frequency characteristic measurement system that directly drives the piezoelectric / electrostrictive actuator 210 without using a vibrator. A piezoelectric / electrostrictive device including a piezoelectric / electrostrictive actuator has a function to vibrate by a reverse piezoelectric effect by itself, unlike an elastic body that does not vibrate by itself, and therefore uses the vibrator 211 shown in FIG. It can be vibrated at least, and a frequency characteristic measurement system can be constructed at a lower cost.

  The frequency characteristic measurement system shown in FIGS. 17A and 17B can directly measure the mechanical vibration itself, and is provided with a target point to be irradiated with a laser and an acceleration sensor. It is preferable in that the vibration distribution can be measured by changing the place.

  FIG. 18 is a configuration diagram illustrating a frequency characteristic measurement system that measures an impedance characteristic that is one of the frequency characteristics of a piezoelectric / electrostrictive device. According to this frequency characteristic measuring system, it is possible to measure the impedance-phase characteristic, admittance-phase characteristic, etc. of the piezoelectric / electrostrictive device. In the vicinity of the resonance frequency, the impedance of the piezoelectric / electrostrictive device changes greatly due to the piezoelectric effect caused by the increase in vibration, so that it is possible to obtain a resonance waveform without using a laser vibrometer. That is, it is preferable in that the measurement can be performed at a lower cost and at a higher speed than the frequency characteristic measurement system shown in FIG. 17 (a) or 17 (b). In addition, impedance measurement can be performed with higher accuracy than a system using a network analyzer.

  19 (a) and 19 (b) show a case where a network analyzer is connected to a piezoelectric / electrostrictive actuator to be inspected through a probe (measuring jig), and a transmitted wave and a reflected wave with respect to an input signal are analyzed. It is a block diagram which shows the example of the system which measures the frequency characteristic of an impedance (a magnitude | size and a phase). FIG. 19A shows an example of a transmission method (transmission method) frequency characteristic measurement system, and FIG. 19B shows an example of a reflection method frequency characteristic measurement system. These frequency characteristic measurement systems can measure frequency characteristics as, for example, gain-phase characteristics, and can also measure impedance-phase characteristics and admittance-phase characteristics using the network analyzer function. is there. According to these frequency characteristic measurement systems, it is possible to perform measurement at a lower cost and at a higher speed than the frequency characteristic measurement system using the impedance analyzer shown in FIG.

  FIG. 23, FIG. 24 (a), FIG. 24 (b), FIG. 24 (c), FIG. 25 (a), FIG. 25 (b), and FIG. It is a chart which shows the example of a measurement of the impedance-phase characteristic (frequency characteristic) of a distortion actuator. The method for detecting the resonance frequency is not limited to the minimum value or minimum value of impedance, the maximum value or minimum value of phase, but the maximum value or minimum value of admittance, the maximum value or minimum value of gain, etc. should be used. Is also possible. The capacitance CP of the piezoelectric / electrostrictive body 79 is measured while applying a voltage between the upper electrode 75 and the lower electrode 77 using an LCR meter or the like. Although the voltage to be applied and its frequency are not limited, it is, for example, a frequency of 1 kHz and a voltage of about 1 V, for example.

  Next, the vibration mode of the plate (plate-like body) at the time of resonance will be described. As already described, in general, the vibration of the plate can be expressed as a (m, n) order vibration mode. FIG. 20 is a diagram illustrating a vibration mode of a rectangular plate. FIG. 21 is a diagram showing a vibration mode in the case of a circular plate. It is possible to specify the vibration mode by the notation of (m, n) in the same manner by the number of nodes in the circumferential direction and the diameter direction of the circular plate instead of the vertical direction and the horizontal direction of the rectangular plate. .

  As in the vibration modes other than m = 3.5 shown in FIG. 20, the direction of vibration is usually reversed when crossing a boundary line that is a node. We found that there is a node in the center of and a vibration mode that vibrates in the same direction on both sides. Since the resonance frequency of this vibration mode is intermediate between the vibration mode of m = 3 and the vibration mode of m = 4, it is expressed as m = 3.5 in this specification, and m = 3.5 in FIG. The vibration mode is shown. The reason for the occurrence of this vibration mode has not been completely elucidated, but the present applicant's piezoelectric / electrostrictive actuator, which is a plate-like body, is piezoelectric on one surface of the vibration part (substrate) as shown in FIG. / The electrostriction actuating part is present and is not symmetrical in the vertical direction, and the vibration part is slightly waved up and down.

  FIG. 22A is a diagram showing a vibration distribution in a vibration mode in which (m, n) = (1,1), and vibration in the AA ′ cross section of the piezoelectric / electrostrictive actuator shown in FIG. Corresponds to the area. In FIG. 22A, ± 1.0 is shown as a support portion, and 0 is shown as the center. Similarly, FIG. 22B is a diagram illustrating the vibration distribution of the vibration mode in which (m, n) = (3, 1), and FIG. 22C is a diagram illustrating (m, n) = (3. It is a figure which shows the vibration distribution of the vibration mode which is 5 and 1). The measurement of the vibration distribution and the specification of the vibration mode are performed in the frequency characteristic measurement system shown in FIGS. 17B to 17A by using a piezoelectric / electrostrictive actuator with a sine wave having a resonance frequency for which the vibration mode is desired. By vibrating the (plate-like body), measuring vibrations at multiple locations of the piezoelectric / electrostrictive actuator using a laser Doppler vibrometer, etc., and analyzing the vibration data comprehensively and observing them with animation, etc. It is possible to specify.

  Next, based on actual measurement data, a method for predicting dimensional deviation and displacement will be specifically described. FIG. 23 is a diagram illustrating an example of the frequency characteristic of the phase value displayed on the screen of the network analyzer. The primary resonance frequency F1 is detected as a frequency indicating the minimum value of the impedance of the lowest frequency and the maximum value of the phase. The primary resonance frequency is the resonance frequency of the vibration mode (1, 1) (vibration in which one antinode is formed) as illustrated in FIG.

  Next, the resonance frequency FA of the higher-order peak A is detected as a frequency indicating the second phase maximum value on the higher frequency side than the resonance frequency F1. The resonance frequency of the higher order peak A is the resonance frequency of the vibration mode (3, 1) (vibration in which three antinodes are formed) as illustrated in FIG. 22B. FR1A = FA / F1 = 1.06 to 1.14.

  Then, the resonance frequency FB of the higher-order peak B is detected as a frequency indicating the maximum value of the third phase on the higher frequency side than the resonance frequency FA. The resonance frequency of the higher order peak B is a resonance frequency of a special vibration mode (3.5, 1) as illustrated in FIG. 22C, and in this example, mainly FR1B = FB / F1. = 1.14 to 1.25.

  FIG. 26 is a graph showing the relationship between the amount of lateral displacement between the piezoelectric / electrostrictive body 79 and the vibrating portion 66 and the amount of displacement of the piezoelectric / electrostrictive actuator having the amount of lateral displacement. In order to clarify the tendency, the analysis was performed including a piezoelectric / electrostrictive actuator with a large deviation amount. FIG. 27 is a graph showing the relationship between the frequency ratio FR1A = FA / F1 and the lateral deviation (absolute value) between the piezoelectric / electrostrictive body 79 and the vibrating portion 66. As clearly shown in FIG. 27, since FR1A and the lateral deviation amount (absolute value) are substantially proportional, as shown in Equation 10, the estimated lateral deviation amount (FR1A) based on a (FR1A) obtained by multiplying FR1A by a coefficient a. Dimension) can be obtained.

  Next, the waviness amount of the vibration part 66 will be described. In FIG. 11, the height H (μm) from the plane connecting both ends of the vibration part 66 to the top of the vibration part 66 is referred to as the undulation amount of the vibration part 66. If the apex of the vibration part is recessed from the plane connecting both ends of the vibration part 66, the height H (swell amount) is represented by a negative numerical value.

  FIG. 29 is a graph showing the relationship between the amount of waviness of the vibrating portion 66 and the amount of displacement of the piezoelectric / electrostrictive actuator having the amount of waviness. In order to clarify the tendency, the analysis was performed including piezoelectric / electrostrictive actuators with large waviness. FIG. 30 is a graph showing the relationship between the frequency ratio FR1B = FB / F1 and the amount of waviness of the vibrating portion 66. As clearly shown in FIG. 30, since FR1B and the amount of swell are approximately proportional, as shown in Equation 11, the predicted amount of swell (size) is obtained based on a (FR1B) obtained by multiplying FR1B by a coefficient a. It is possible.

Further, as clearly shown in FIG. 26, the lateral deviation amount and the displacement amount are approximately proportional, and as clearly shown in FIG. 29, the swell amount and the displacement amount are in a relationship represented by a quadratic polynomial. As shown in FIG. 2, based on a (FR1A) obtained by multiplying FR1A by a coefficient a, c (FR1B) obtained by multiplying FR1B by a coefficient c, and b (FR1B) ² obtained by multiplying the square of FR1B by a coefficient b. (An additional capacitance CP can be added), and the predicted displacement can be obtained. In the manufacturing process, for example, when the piezoelectric / electrostrictive body 79 is formed by printing or the like, the printing position of the piezoelectric / electrostrictive body 79 is changed so that the amount of lateral displacement between the piezoelectric / electrostrictive body 79 and the vibrating portion 66 is changed. It is possible to adjust the predicted displacement amount by slightly changing.

Further, as shown in Expression 13, e (F1) obtained by multiplying F1 by a coefficient e, a (FR1A) obtained by multiplying FR1A by a coefficient a, c (FR1B) obtained by multiplying FR1B by a coefficient c, and FR1B. Based on b (FR1B) ² obtained by multiplying the square of x by a coefficient b (capacitance can be further added), the predicted displacement amount can be obtained. In the manufacturing process, for example, when the piezoelectric / electrostrictive body 79 is formed by printing or the like, the printing position of the piezoelectric / electrostrictive body 79 is changed so that the amount of lateral displacement between the piezoelectric / electrostrictive body 79 and the vibrating portion 66 is changed. The predicted displacement can be adjusted by making a fine change.

  FIG. 32A is a graph of the predicted displacement amount and the actually measured displacement amount when the displacement is predicted by a linear expression of only the capacity CP (predicted displacement amount = a × CP + b, where a and b are coefficients). FIG. 32B is a graph showing the relationship between the predicted displacement amount and the actually measured displacement amount when the displacement is predicted by Equation (13). This graph shows the relationship between 16 estimated piezoelectric / electrostrictive actuators having the same form as the piezoelectric / electrostrictive actuator 20 and the respective measured displacements measured by a laser Doppler vibrometer. Is roughly proportional. 32B shows that the correlation between the predicted displacement amount and the actually measured displacement amount is better than that in FIG. 32A, and the displacement can be predicted with higher accuracy.

  In the above inspection, attention is paid to the resonance frequency and the resonance waveform applied to the vibration mode (1, 1), the vibration mode (3, 1), and the vibration mode (3.5, 1). It is possible to inspect by paying attention to the resonance frequency and the resonance waveform.

FIGS. 24A to 24C are charts showing measurement examples of frequency characteristics of impedance-phase of the piezoelectric / electrostrictive actuator. FIG. 24A shows the frequency characteristics when no lateral deviation occurs (the deviation amount is 0 μm), and FIG. 24B shows the frequency characteristics when the lateral deviation is (relatively) small. c) shows frequency characteristics when the lateral deviation is (relatively) large. In any case, the left peak in the figure indicates the primary peak, and the right peak indicates the high order peak C. The primary peak is a mode of (m, n) = (1, 1), and the high order peak C is a vibration mode of (m, n) = (1, 2).

  As shown in FIG. 24A, in the piezoelectric / electrostrictive actuator in which no lateral deviation occurs, there is a peak of the resonance frequency applied to the vibration mode (1, 1) in the low frequency region. There are no noticeable peaks in the area. On the other hand, as shown in FIGS. 24B and 24C, in the piezoelectric / electrostrictive actuator in which the lateral displacement occurs, the vibration mode (1, 2) is obtained in a high frequency region (for example, 4.5 to 5 MHz). 2), the peak of the resonance frequency (resonance waveform) is generated. As clearly shown in the comparison between FIG. 24B and FIG. 24C, the peak increases as the amount of lateral deviation increases. And the area SC of the resonance waveform from the frequency R to the frequency T increases. Further, as the lateral shift amount increases, the peak height PK1 (resonance waveform) of the resonance frequency (resonance waveform) applied to the vibration mode (1, 1) appearing in the low frequency region, or the resonance waveform between the frequency Q and the frequency P. The area S1 is reduced.

  Also in the impedance characteristic, the basic tendency is the same as the phase characteristic. That is, as shown in FIG. 24A, in the piezoelectric / electrostrictive actuator in which no lateral deviation occurs, the maximum value E1 and the minimum value E2 generated by resonance in the vibration mode (1, 1) in the low frequency region. And a stepped waveform is not seen in a constant region having a high frequency. On the other hand, as shown in FIGS. 24B and 24C, in the piezoelectric / electrostrictive actuator in which the lateral displacement occurs, the vibration mode (1, 2) is obtained in a high frequency region (for example, 4.5 to 5 MHz). As shown in the comparison between FIG. 24B and FIG. 24C, the stepped waveform generated by the resonance in 2) is seen, and the maximum value E3 increases as the amount of lateral deviation increases. The difference from the minimum value E4 increases.

  In FIG. 28A, a curve 181 indicates the relationship between the lateral shift amount and the height PKC of the high-order peak C, and a curve 182 indicates the relationship between the lateral shift amount and the primary peak height PK1. In FIG. 28B, a curve 183 shows the relationship between the amount of lateral deviation and the area SC of the high-order peak C, and a curve 184 shows the relationship between the amount of lateral deviation and the area S1 of the primary peak. Further, in FIG. 28C, a curve 185 shows the relationship between the lateral deviation amount and the peak height ratio PKC / PK1, and a curve 186 shows the lateral deviation amount and peak area ratio (area ratio) SC / S1. Shows the relationship. As clearly shown in FIGS. 28A to 28C, the peak height PKC and the area SC are large (the detection sensitivity is high) when the lateral deviation amount is small, and the peak is large when the lateral deviation amount is large. The height ratio PKC / PK1 and the area ratio SC / S1 increase (the detection sensitivity is high).

  A phenomenon such as an increase in the peak height (resonance waveform) of the vibration mode (1, 2) due to the lateral shift can be explained for the following reason. That is, when the piezoelectric / electrostrictive actuator is arranged without lateral displacement with respect to the vibrating part, the center of gravity of the piezoelectric / electrostrictive actuator as a structure coincides with the center of vibration. In addition, the bending displacement close to the vibration mode (1, 1) is excited by the expansion / contraction of the piezoelectric / electrostrictive operating portion. That is, the center of the vibration part is large and the displacement is excited. In this case, odd-order vibration modes (3, 1), (5, 1), (7, 1), (1, 3), etc. in which the center of the vibration part greatly vibrates are relatively easily excited. However, even-order vibration modes (2, 1), (4, 1), (1, 2), etc. in which the center of the vibration part is a node are difficult to be excited. Actually, vibration modes (1, 2) as shown in FIG. 24 (a) are hardly observed. On the other hand, when a lateral shift occurs, the center of gravity position between the center of vibration and the piezoelectric / electrostrictive actuator is shifted, and the even-order mode is excited. As the deviation increases, the even-order mode increases. The lateral shift in question is a positional shift in the BB ′ cross section of the piezoelectric / electrostrictive actuator shown in FIG. 1, and a vibration mode (1, 2) having a node in the center of a narrow lateral direction (see FIG. 20). Is strongly excited. Similarly, in the case of the misalignment in the AA ′ cross section of FIG. 1, the (2, 1) mode is strongly excited, but the misalignment in this direction has almost no adverse effect on the displacement. Although this is not a problem in the book, this concept can be applied as a dimensional deviation inspection. The method of predicting lateral deviation and displacement using the high-order peak C shown in FIGS. 24B and 24C is compared with the method of predicting using the high-order peak A shown in FIG. , Because there are relatively few noise peaks (resonance waveforms) near each peak (resonance waveform) and there is a low probability of erroneous detection of another unintended peak (resonance waveform). It is possible to predict a lateral shift, which is more preferable. Since the prediction formula for the amount of lateral deviation due to the higher-order peak C can be regarded as a straight line in the vicinity of the origin from FIG. 28A, it can be expressed by a simple expression such as Expression (14), for example.

25 (a), 25 (b), and 25 (c) are diagrams illustrating an example of the frequency characteristic of the phase value displayed on the screen of the network analyzer, and FIG. 25 (a) illustrates the vibration unit. FIG. 25 (b) shows the frequency characteristics of a piezoelectric / electrostrictive actuator (see FIG. 5) having a downward undulation in FIG. FIG. 25C shows the frequency characteristics of the piezoelectric / electrostrictive actuator (see FIG. 10) in the form in which the vibrating portion has upward swell. As shown in FIGS. 25A, 25B, and 25C, the resonance frequency FD of the higher-order peak D is detected at a frequency of 8 to 9 MHz, and the resonance frequency FE of the higher-order peak E is detected. Is detected at a frequency of 10 to 11 MHz. The resonance frequency of the higher order peak D is the resonance frequency of the vibration mode (1, 3), and the resonance frequency of the higher order peak E is the resonance frequency of the vibration mode (3.5, 3). The frequency ratio FRDE (FRDE = FE / FD) based on these two resonance frequencies is related to the amount of waviness of the piezoelectric / electrostrictive actuator, and the piezoelectric / electrostrictive actuator is obtained by obtaining the frequency ratio FRDE from the resonance frequencies FE and FD. The amount of swell can be predicted. That is, although there is a slight shift in value, it is possible to predict the amount of swell, the amount of displacement, and the like by a calculation formula almost the same as that of FR1B described above. 25 (a), 25 (b), and 25 (c), the method of predicting the undulation amount using the higher order peak D and the higher order peak E is the primary peak shown in FIG. Compared with the method using the higher order peak B, there are relatively few noise peaks (resonance waveform) near each peak (resonance waveform), and the probability of erroneous detection of another peak is low. Therefore, it is possible to predict the swell amount with high sensitivity and high accuracy, which is more preferable. FIG. 31 is a graph showing the relationship between the frequency ratio FRDE and the amount of waviness of the vibrating portion applied to the piezoelectric / electrostrictive actuator. Since the prediction formula of the undulation amount due to the higher-order peaks D and E can be approximated as a straight line from FIG. 31, it can be expressed by a simple expression such as Expression 15.

  Further, the prediction formula of the displacement amount due to the higher-order peaks C, D, E can be expressed by, for example, an equation such as Equation 16 in consideration of the relationship between the undulation amount and the displacement amount of a quadratic curve. It is.

  When the predicted lateral deviation amount, predicted swell amount, and predicted displacement amount are obtained, based on these, it is determined whether the produced piezoelectric / electrostrictive actuator 20 is a good product or a defective product, and the inspection is completed. . Only the piezoelectric / electrostrictive actuator 20 that has passed the inspection is shipped.

  Conventionally, since the piezoelectric / electrostrictive actuator is inspected based only on the capacitance of the piezoelectric / electrostrictive body, the piezoelectric / electrostrictive actuator is composed of other elements constituting the piezoelectric / electrostrictive actuator, that is, a vibration part and a support part. Differences between products such as substrates were not reflected in the inspection results. Therefore, although there was a limit to the improvement of inspection accuracy, the above inspection was obtained by actually vibrating the piezoelectric / electrostrictive actuator on which the predicted lateral deviation amount, predicted undulation amount, and predicted displacement amount were produced. These all reflect all the elements that comprise the piezoelectric / electrostrictive actuator (including those that cannot be predicted), so that variations in dimensions and displacement can be reliably identified, and it will take more time to inspect than before. The determination of whether the product is non-defective with high accuracy can be made more accurately. Since the manufactured product is merely vibrated, and the piezoelectric / electrostrictive actuator is not destroyed or decomposed, the inspection does not take much time. For example, a micro switch in which a non-defective piezoelectric / electrostrictive actuator that has passed the inspection is used as an actuator section has a displacement amount of the vibrating section within a certain range, thereby suppressing variations in switch operation.

  By the way, the dimensions such as the shift amount and the waviness amount have a great influence on the detection sensitivity of the piezoelectric / electrostrictive sensor as well as the actuator displacement amount of the piezoelectric / electrostrictive actuator. That is, in the piezoelectric / electrostrictive sensor, it is possible to predict and estimate the detection sensitivity with higher accuracy by performing multivariate analysis or the like in combination with capacitance, resonance frequency, resonance frequency ratio, and the like.

  The present invention can also be effectively used for inspection of a piezoelectric / electrostrictive actuator set in which a plurality of piezoelectric / electrostrictive actuators are arranged vertically and horizontally. In other words, the variation in the dimensional deviation of each piezoelectric / electrostrictive actuator in the piezoelectric / electrostrictive actuator set is the characteristic variation of the piezoelectric / electrostrictive actuator set. When examining the size of the variation and trying to use it for each application, the resonance frequency, resonance frequency ratio, resonance waveform peak height, area, etc. of the primary and higher order resonance modes, etc. Thus, it is possible to accurately predict the characteristic variation of the piezoelectric / electrostrictive actuator set.

  Next, calculation is performed by adding the frequency ratio FR1A and the frequency ratio FR1B and, if necessary, the capacitance CP to predict the dimensions of the piezoelectric / electrostrictive actuator 20 and the displacement amount of the piezoelectric / electrostrictive actuator 20. Therefore, an elastic body (piezoelectric / electrostrictive actuator) size prediction program and a piezoelectric / electrostrictive actuator displacement prediction program according to the present invention will be described.

  Hereinafter, first, a displacement amount prediction program (also simply referred to as a displacement amount prediction program) of the piezoelectric / electrostrictive actuator according to the present invention will be described. FIG. 33A and FIG. 33B are configuration diagrams of a computer system in which a displacement amount prediction program is incorporated. A computer system 10 shown in FIG. 33 (a) mainly includes a central processing unit 1, a storage device 2 (main memory), an input device 4, and an output device 5. The displacement amount prediction program according to the present invention is a program for causing a computer to function as a predetermined means in order to predict the displacement amount of a piezoelectric / electrostrictive actuator including a piezoelectric / electrostrictive body and two or more electrodes. is there. The displacement amount prediction program according to the present invention is stored in the storage device 2, and the central processing unit 1 issues a command to other devices constituting the computer system 10 based on this program.

  The central processing unit 1 calculates a predicted displacement amount of the piezoelectric / electrostrictive actuator based on a calculation formula to be applied to the piezoelectric / electrostrictive actuator that is to predict the displacement amount in accordance with a command of the displacement amount prediction program. Next, the central processing unit 1 outputs the obtained predicted displacement amount of the piezoelectric / electrostrictive actuator to a printer or CRT (screen) in accordance with a command of the displacement amount prediction program. The calculation formula can be incorporated in the displacement amount prediction program. Further, the calculation formula is not limited to the example, and can be changed according to the characteristics of the inspection object such as an exponential function or a higher order polynomial.

  In the computer system 10, a case where the predicted displacement amount is obtained by using a specific calculation formula will be described. Information on the resonance frequency, peak height, and area of the first and higher order resonance modes when the piezoelectric / electrostrictive actuator for which the predicted displacement is to be calculated is vibrated is obtained from the keyboard and network analyzer. Etc. are input. The central processing unit 1 receives a command from the displacement amount prediction program in the storage device 2 and calculates a resonance frequency ratio, a peak height ratio, an area ratio, and the like.

  Further, the central processing unit 1 receives the command of the displacement amount prediction program in the storage device 2 and calculates Equations 12 and 13 which are calculation equations for calculating the predicted displacement amount applied to the piezoelectric / electrostrictive actuator. Based on this, a predicted displacement amount of the piezoelectric / electrostrictive actuator is calculated. When the capacitance is used to obtain the predicted displacement amount (corresponding to Equation 4), the capacitance CP of the piezoelectric / electrostrictive body of the piezoelectric / electrostrictive actuator for which the predicted displacement amount is to be calculated is Input from a keyboard, LCR meter or the like. The calculated predicted displacement amount is output as digital data or analog data by the central processing unit 1 to a printer, a CRT (screen), or the like according to a command from the displacement amount prediction program.

  A computer system 330 shown in FIG. 33B is obtained by adding a pass / fail sorting device (robot) in addition to the computer system shown in FIG. For each measured object, the displacement predicted based on the displacement prediction program is stored in the storage device, and pass / fail judgment information based on the specified threshold value is also stored in the storage device. The pass / fail sorting device (robot) sorts the specimen (piezoelectric / electrostrictive actuator product) based on the pass / fail judgment information. For example, the non-defective product is replaced with the non-defective product tray, the defective product is replaced with the defective product tray, etc. Perform the operation.

  The elastic body size prediction program (also simply referred to as a size prediction program) according to the present invention is a size (shift) applied to the piezoelectric / electrostrictive body 79 of the piezoelectric / electrostrictive actuator 78 and the vibrating portion 66 of the base body 44, which are elastic bodies. This is a program for causing a computer to function as a predetermined means in order to predict (amount and undulation amount). The dimension prediction program according to the present invention is stored in the storage device 2 in accordance with the above-described displacement amount prediction program except that Formula 1 is used to calculate the predicted dimension. The processing device 1 issues commands to other devices constituting the computer system 10, and detailed description thereof is omitted.

  The piezoelectric / electrostrictive actuator inspection method, inspection apparatus, and displacement amount prediction program according to the present invention have been described with reference to an example of the piezoelectric / electrostrictive actuator. Also, the piezoelectric / electrostrictive sensor targeted by each of the inspection apparatus and the detection sensitivity prediction program has only a difference between electrical / mechanical conversion and mechanical / electrical conversion. It is the same mode.

  The piezoelectric / electrostrictive actuators that can be targeted by the piezoelectric / electrostrictive actuator inspection method, inspection apparatus, and displacement amount prediction program according to the present invention are each an elastic piezoelectric / electrostrictive body and two or more. Since it comprises an electrode, it corresponds to a structure having two or more elastic bodies. In this specification, as a piezoelectric / electrostrictive actuator, in addition to a piezoelectric / electrostrictive operating part composed of a piezoelectric / electrostrictive body and two or more electrodes, it is an elastic body and is composed of a vibrating part and a supporting part. In the example, the piezoelectric / electrostrictive operation portion, the vibration portion, and the support portion are shown as one elastic body.

  The elastic body that can be targeted by each of the elastic body inspection method, inspection apparatus, and size prediction program according to the present invention is an object that exhibits non-plastic elasticity, and is at least a structure composed of two or more elastic bodies. The elastic body is not limited to a piezoelectric / electrostrictive body (piezoelectric / electrostrictive operating portion) and a ceramic substrate (vibrating portion).

  Further, a piezoelectric / electrostrictive device inspection method, an inspection apparatus, and a displacement amount prediction program according to the present invention, and a piezoelectric / electrostrictive device inspection method according to the present invention, The piezoelectric / electrostrictive sensor targeted by each of the inspection device and the detection sensitivity prediction program indicates a unit that performs a collective function by using a charge / electric field induced by strain or stress induced by an electric field. / Consists of an electrostrictive body and at least a pair of electrodes, and in a narrow sense, generates an amount of charge induced by an inverse piezoelectric effect or stress that generates a strain amount approximately proportional to an applied electric field. It is not limited to piezoelectric / electrostrictive actuators that use the electrostrictive effect that generates a piezoelectric effect or a strain that is roughly proportional to the square of the applied electric field. , Anti-ferroelectric phase is seen in the anti-ferroelectric material - the phase transition between the ferroelectric phase, also includes the piezoelectric / electrostrictive actuator using a phenomenon like. Also, whether or not the polarization process is performed is appropriately determined based on the properties of the material used for the piezoelectric / electrostrictive body constituting the piezoelectric / electrostrictive actuator.

  The elastic body inspection method, inspection apparatus, and size prediction program, and the piezoelectric / electrostrictive actuator inspection method, inspection apparatus, and displacement amount prediction program according to the present invention include, for example, a measuring instrument, an optical modulator, and an optical switch. , Electrical switches, micro relays, micro valves, transfer devices, displays, projectors and other image display devices, image drawing devices, micro pumps, droplet ejection devices, micro mixing devices, micro stirring devices, micro reaction devices, etc. It can be suitably used as an inspection means for various piezoelectric / electrostrictive actuators. Also, the inspection method, inspection apparatus, and detection sensitivity prediction program for piezoelectric / electrostrictive sensors according to the present invention are used to inspect various piezoelectric / electrostrictive sensors used for detecting fluid characteristics, sound pressure, minute weight, acceleration, and the like. It can be suitably used as a means.

Claims (14)

An inspection method of a piezoelectric / electrostrictive actuator comprising one or more piezoelectric / electrostrictive bodies and two or more electrodes,
The piezoelectric / electrostrictive actuator includes a base body and a piezoelectric / electrostrictive operating portion, and the base body integrally includes a thick support portion having a cavity and a vibration portion covering the cavity. The piezoelectric / electrostrictive actuating part is formed, and includes the one or more piezoelectric / electrostrictive bodies and the two or more electrodes laminated with the piezoelectric / electrostrictive bodies sandwiched therebetween. When an electric field is generated between the electrodes sandwiching the strain body, the piezoelectric / electrostrictive body is deformed, and the vibration part is displaced in the vertical direction.
Observe the frequency characteristics when vibrating the piezoelectric / electrostrictive actuator,
Frequency characteristics of a reference piezoelectric / electrostrictive body having at least one piezoelectric / electrostrictive body and two or more electrodes of known dimensions, and dimensions obtained by vibrating the reference piezoelectric / electrostrictive actuator. A method for inspecting a piezoelectric / electrostrictive actuator that uses data representing a relationship between the two and predicts a displacement amount of the piezoelectric / electrostrictive actuator based on a frequency characteristic observed by vibrating the piezoelectric / electrostrictive actuator. The frequency characteristics include a resonance frequency Fx of one order and a resonance frequency Fy of another order, and one or more frequency ratios FRxy (FRxy = Fy / Fx) obtained by them to one or more frequency differences FDxy (FDxy = FDxy = 2. The method for inspecting a piezoelectric / electrostrictive actuator according to claim 1 , wherein the inspection method is any one of Fy-Fx). The frequency characteristic includes a peak height PKx, an area Sx, and a difference between a maximum value and a minimum value of a resonance waveform of one order, and between the resonance waveform of the first order and a resonance waveform of another order. , Peak height ratio PKRxy, peak height difference PKDxy, area ratio SRxy, area difference SDxy, difference between local maximum and local minimum, and difference between local maximum and local minimum The method for inspecting a piezoelectric / electrostrictive actuator according to claim 1 . An inspection method for a piezoelectric / electrostrictive sensor comprising one or more piezoelectric / electrostrictive bodies and two or more electrodes,
The piezoelectric / electrostrictive sensor includes a base and a piezoelectric / electrostrictive operating unit, and the base integrally includes a thick support portion having a cavity and a vibration unit covering the cavity. The piezoelectric / electrostrictive actuating part is formed, and includes the one or more piezoelectric / electrostrictive bodies and the two or more electrodes laminated with the piezoelectric / electrostrictive bodies sandwiched therebetween. When an electric field is generated between the electrodes sandwiching the strain body, the piezoelectric / electrostrictive body is deformed, and the vibration part is displaced in the vertical direction.
Observe the frequency characteristics when vibrating the piezoelectric / electrostrictive sensor,
A frequency characteristic of a reference piezoelectric / electrostrictive sensor having at least one piezoelectric / electrostrictive body and two or more electrodes with known dimensions, and a sensor obtained by vibrating the reference piezoelectric / electrostrictive sensor. Piezoelectric / electrostrictive sensor inspection method for predicting detection sensitivity of the piezoelectric / electrostrictive sensor based on frequency characteristics observed by vibrating the piezoelectric / electrostrictive sensor using data representing the relationship between dimensions . The frequency characteristics include a resonance frequency Fx of one order and a resonance frequency Fy of another order, and one or more frequency ratios FRxy (FRxy = Fy / Fx) obtained by them to one or more frequency differences FDxy (FDxy = FDxy = 5. The method for inspecting a piezoelectric / electrostrictive sensor according to claim 4 , wherein the inspection method is any one of Fy-Fx). The frequency characteristic includes a peak height PKx, an area Sx, and a difference between a maximum value and a minimum value of a resonance waveform of one order, and between the resonance waveform of the first order and a resonance waveform of another order. , Peak height ratio PKRxy, peak height difference PKDxy, area ratio SRxy, area difference SDxy, difference between local maximum and local minimum, and difference between local maximum and local minimum The method for inspecting a piezoelectric / electrostrictive sensor according to claim 4 . An apparatus for inspecting a piezoelectric / electrostrictive actuator comprising one or more piezoelectric / electrostrictive bodies and two or more electrodes,
The piezoelectric / electrostrictive actuator includes a base body and a piezoelectric / electrostrictive operating portion, and the base body integrally includes a thick support portion having a cavity and a vibration portion covering the cavity. The piezoelectric / electrostrictive actuating part is formed, and includes the one or more piezoelectric / electrostrictive bodies and the two or more electrodes laminated with the piezoelectric / electrostrictive bodies sandwiched therebetween. When an electric field is generated between the electrodes sandwiching the strain body, the piezoelectric / electrostrictive body is deformed, and the vibration part is displaced in the vertical direction.
Means for observing frequency characteristics when the piezoelectric / electrostrictive actuator is vibrated;
Frequency characteristics of a reference piezoelectric / electrostrictive actuator having at least one piezoelectric / electrostrictive body and two or more electrodes of known dimensions, and dimensions obtained by vibrating the reference piezoelectric / electrostrictive actuator. Means for predicting the displacement amount of the piezoelectric / electrostrictive actuator based on frequency characteristics observed by vibrating the piezoelectric / electrostrictive actuator using data representative of the relationship between the piezoelectric / electrostrictive actuator ;
A piezoelectric / electrostrictive actuator inspection apparatus comprising: The frequency characteristics include a resonance frequency Fx of one order and a resonance frequency Fy of another order, and one or more frequency ratios FRxy (FRxy = Fy / Fx) obtained by them to one or more frequency differences FDxy (FDxy = FDxy = The inspection apparatus for a piezoelectric / electrostrictive actuator according to claim 7 , wherein the inspection apparatus is any one of Fy−Fx). The frequency characteristic includes a peak height PKx, an area Sx, and a difference between a maximum value and a minimum value of a resonance waveform of one order, and between the resonance waveform of the first order and a resonance waveform of another order. , Peak height ratio PKRxy, peak height difference PKDxy, area ratio SRxy, area difference SDxy, difference between local maximum and local minimum, and difference between local maximum and local minimum The inspection apparatus for a piezoelectric / electrostrictive actuator according to claim 7 . An apparatus for inspecting a piezoelectric / electrostrictive sensor comprising one or more piezoelectric / electrostrictive bodies and two or more electrodes,
The piezoelectric / electrostrictive sensor includes a base and a piezoelectric / electrostrictive operating unit, and the base integrally includes a thick support portion having a cavity and a vibration unit covering the cavity. The piezoelectric / electrostrictive actuating part is formed, and includes the one or more piezoelectric / electrostrictive bodies and the two or more electrodes laminated with the piezoelectric / electrostrictive bodies sandwiched therebetween. When an electric field is generated between the electrodes sandwiching the strain body, the piezoelectric / electrostrictive body is deformed, and the vibration part is displaced in the vertical direction.
Means for observing frequency characteristics when the piezoelectric / electrostrictive sensor is vibrated;
Between the frequency characteristic of a reference piezoelectric / electrostrictive sensor having at least one piezoelectric / electrostrictive body and two or more electrodes of known dimensions and the dimensions obtained by vibrating the piezoelectric / electrostrictive sensor. means for relationship using data representative of, for predicting the sensitivity of the piezoelectric / electrostrictive sensor based on the frequency characteristic observed by vibrating the piezoelectric / electrostrictive sensor,
A piezoelectric / electrostrictive sensor inspection apparatus comprising: The frequency characteristics include a resonance frequency Fx of one order and a resonance frequency Fy of another order, and one or more frequency ratios FRxy (FRxy = Fy / Fx) obtained by them to one or more frequency differences FDxy (FDxy = FDxy = The inspection apparatus for a piezoelectric / electrostrictive sensor according to claim 10 , wherein the inspection apparatus is any one of Fy−Fx). The frequency characteristic includes a peak height PKx, an area Sx, and a difference between a maximum value and a minimum value of a resonance waveform of one order, and between the resonance waveform of the first order and a resonance waveform of another order. , Peak height ratio PKRxy, peak height difference PKDxy, area ratio SRxy, area difference SDxy, difference between local maximum and local minimum, and difference between local maximum and local minimum The inspection apparatus for a piezoelectric / electrostrictive sensor according to claim 10 . A base body and a piezoelectric / electrostrictive operating portion, and the base body is formed by integrally forming a thick support portion having a cavity and a vibrating portion covering the cavity, and The electrostrictive operation unit includes one or more piezoelectric / electrostrictive bodies and two or more electrodes stacked with the piezoelectric / electrostrictive bodies sandwiched therebetween, and an electric field is generated between the electrodes sandwiching the piezoelectric / electrostrictive bodies. In order to predict the amount of displacement of the piezoelectric / electrostrictive actuator that causes the piezoelectric / electrostrictive body to be deformed and generate a vertical displacement in the vibrating portion ,
Means for inputting the frequency characteristics of the piezoelectric / electrostrictive actuator to calculate the predicted displacement;
Means for obtaining a predicted displacement amount of the piezoelectric / electrostrictive actuator based on a calculation formula of a predicted displacement amount;
Means for outputting a predicted displacement amount of the obtained piezoelectric / electrostrictive actuator;
As a program for predicting the displacement of a piezoelectric / electrostrictive actuator to function. A base body and a piezoelectric / electrostrictive operating portion, and the base body is formed by integrally forming a thick support portion having a cavity and a vibrating portion covering the cavity, and The electrostrictive operation unit includes one or more piezoelectric / electrostrictive bodies and two or more electrodes stacked with the piezoelectric / electrostrictive bodies sandwiched therebetween, and an electric field is generated between the electrodes sandwiching the piezoelectric / electrostrictive bodies. In order to predict the detection sensitivity of the piezoelectric / electrostrictive sensor that causes the piezoelectric / electrostrictive body to be deformed when the piezoelectric / electrostrictive body is deformed and causes the vibration part to move in the vertical direction ,
Means for inputting the frequency characteristics of the piezoelectric / electrostrictive sensor to calculate the predicted detection sensitivity;
Means for obtaining a predicted detection sensitivity of the piezoelectric / electrostrictive sensor based on a calculation formula of a predicted detection sensitivity;
Means for outputting a predicted detection sensitivity of the obtained piezoelectric / electrostrictive sensor;
As a detection sensitivity prediction program for a piezoelectric / electrostrictive sensor for functioning.

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